1. Field of the Invention
This invention relates to mechanism for continuously constructing reinforced concrete tunnels.
2. Prior Art
In the usual tunnel construction method, a great quantity of expensive agglomerating material is poured into the ground. In a prior art method of tunnel construction, the tunnel construction is advanced while assembling prefabricated concrete blocks in a bore formed to a somewhat excess size. In this case, the obtainable structure is mechanically weak because it is formed as its individual components or elements are connected to one after another.
Another drawback inherent in the prior art tunnel construction method is that a physical gap is formed between the tunnel body and the ground, thus giving rise to deformation of the ground and consequent accidents. A prelining process is a further prior art method of tunnel construction. Again in this case, a groove is formed around the tunnel face and then filled with concrete before digging further bore, and the process has similar inherent drawbacks. Further, if there is a spring in the work site of digging, it results in a difficult construction work, dictating a great deal of work expenditures and long time to effect digging for a unit distance.